Detectives were investing multiple crime scenes in two counties Wednesday that were believed to be connected to a homicide.
The four teenagers, all students at Tustin High, were arrested Wednesday.
Police are on the lookout for an apparently unarmed man who robbed a bank in the city of Tustin.
A transient and registered sex offender is scheduled to appear in court Friday after being arrested on suspicion of robbing a convenience store in Tustin at gunpoint.
A gunman killed three people and injured three others before turning the gun on himself during a shooting spree Tuesday in Orange County.
Authorities say they have shot and wounded a man in Tustin while handling a “disturbance call.”